Hi Chris, sorry to hear that.
The first thing to check is the thermostat. You will need a meter for that.
But in most cases when you get this problem on this one, it will be the main board and thermostat that I would replace at the same time.
If you want to fix this, these parts are easy to change out if you are handy and have a few basic hand tools. I will help all the way as well.
The best way to get those components is: http://www.thecaravanspecialists.co.uk/fridges-and-spares/thetford-fridge-spares
Its best to call them to place the order because they ship same day if you call;-)
The Caravan Specialists
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